Certaines parties de cette page sont affichées en anglais en attendant la traduction.
Reproductive regulation: motivation, capacity and care
How a shared biological state can produce coordinated—and selectively different—behavioural outcomes.
Reproduction is regulated before a pregnancy begins. Biological state shapes what attracts attention, whether an approach occurs, how another individual responds and which physiological transitions can succeed. The same system also regulates care. BERM connects these three branches to explain both shared changes and the outputs that remain intact.
Three branches from a shared receiving state
The physical input enters BERM through its conditional receiving response, then the existing calcium, redox, clock, metabolic and hormone-receptor states. The experiments here identify downstream biological and social transitions. They give the model a concrete structure for reproductive regulation; the geometric input and its tissue-specific calibration remain the separate upstream link.
Receiving state + hormonal timing + learned history + present context
Motivation and realisation
Desire and cue response → approach → another individual’s response → a realised encounter or attempt.
Measure desire, action and opportunity separately.
Physiological capacity
GnRH/LH responsiveness → gonadal function and reserve → the biological success of an encounter.
Measure current hormone levels, stimulated response and functional success separately.
Realised encounters and conditional biological success → reproductive timing and births
Caregiving and feedback
Sensitivity to caregiving cues → directed care → changed contact and learning → later responses.
Measure the amount and target of care alongside reproductive activity.
Care → later contact, learning and receiving state
A reproductive brake can be selective
A biological intervention can reduce reproductive-axis activation and sexually directed behaviour while several other functions remain available.
In naked mole-rats, RFRP-3 administration after colony removal prevented a progesterone rise and reduced opposite-sex genital investigation. Other social investigation, movement and several additional responses remained intact. The experiment locates a selective output pattern: a general loss of activity is unnecessary to explain the reproductive change. Peragine 2017i.
Marmoset removal and return experiments place social context upstream of LH and ovulation. Together with the hormone-challenge literature, they identify reproductive-axis responsiveness more precisely than a universal high-cortisol state. For BERM, selectivity adds explanatory power: a shared receiving state can change particular target circuits while preserving other functions. Abbott 1988i.
One hormonal signal, different target circuits
Reproductive-axis activation and caregiving can diverge because the same hormonal system acts through distinct receiving pathways.
Prolactin → kisspeptin → reproductive-axis response
In mice, prolactin exposure reduced kisspeptin expression and reproductive-axis activity; kisspeptin restored ovarian cycling. In women with hyperprolactinaemia, repeated kisspeptin administration increased LH pulses without a significant overall reduction in prolactin. The human endpoint was a pulse response.
Prolactin-sensitive MPOA–VTA → offspring contact
A separate mouse study located a prolactin-sensitive circuit supporting offspring contact and a related dopamine response. Activating the pathway increased contact even in females that had not given birth. Circuit-specific intervention identifies a caregiving route.
BERM synthesis: the shared hormone connects these experiments at a named biological variable. Different receptors, circuits and reproductive phases explain why care can be maintained or strengthened while reproductive-axis activation falls. Kohl’s projection-specific work and Ammari’s pregnancy-related circuit plasticity further separate components and timescales of care. Kohl 2018i; Ammari 2023i.
The amount of care and its target are different outcomes. Own-child care, care for another child and care for an animal require their own contact histories and measures. A caregiving relationship becomes informative about reproductive regulation when it is joined to the same person’s physiological and behavioural sequence.
The order of change helps locate the gate
Social behaviour, hormone pulses, gonadal reserve and a birth occupy different clocks. Follow each measured variable through time instead of assigning one recovery time to the whole profile.
Behaviour can change before slow tissue remodelling
Social opportunity in cichlids produced rapid behavioural and local gene-expression responses; related work measured gonadotropin changes within 30 minutes. These are different measurements in the same research programme, with their own experimental samples.
Behaviour can also outlast measured hormone differences
A visual social cue maintained subordinate behaviour across seven days while measured physiological differences were transient or absent by the final time point. The visible behaviour therefore did not identify the entire current physiological state.
Reserve can remain available during social suppression
Suppressed male cichlids retained spermatogenesis and could fertilise within hours of a social opportunity. A suppressed reproductive role and complete loss of biological capacity are distinct states.
Realised reproductive transitions are followed across longer intervals
Cebu analyses connect fatherhood, testosterone and sexual activity within one cohort. Friendship and workplace studies add the timing of later reproductive transitions. Their longer follow-up supplies a different measurement scale from an acute hormone challenge.
Read the evidence as a matrix of measured transitions
Compare the intervention, biological measurement, observed output and time course. The research family stays attached when several papers describe the same cohort or experimental programme.
Certaines parties de cette page sont affichées en anglais en attendant la traduction.
31 studies · 20 research families
Families identify shared cohorts and research lineages; these counts do not assume independent replication.
Component experiments manipulate a biological or social input. An experiment in a wild animal group retains that classification: the measured intervention determines its place in the chain.
Bell et al. (2014)Component experimentWild meerkats; 12 groupsKalahari meerkat studies
Input or comparison
Contraception versus saline in a crossover design
Measured change and output
Suppressing subordinate reproduction increased pup feeding and reduced dominant aggression and eviction.
Biological and contextual measurements
- Pregnancy
- Social status, eviction or aggression
Observed outcomes
- Observed caregiving
- Availability of reproductive interactions
Time course
Two nine-month periods, 2009–2011; 59 dominant reproductive attempts
Shared data and research lineage
Shared research system; contraception and eviction studies are different designs.
Scope of the finding
Group opportunities and pregnancy costs also changed; the experiment does not isolate intrinsic caregiving motivation.
Source and corrections
Young et al. (2006)Observational studySubordinate female meerkatsKalahari meerkat studies
Input or comparison
Natural eviction followed longitudinally; GnRH challenge
Measured change and output
Eviction coincided with higher glucocorticoids, reduced pituitary response and poorer reproductive outcomes.
Biological and contextual measurements
- Cortisol or glucocorticoid metabolites
- Response to a GnRH challenge
- Social status, eviction or aggression
Observed outcomes
- Pregnancy
- LH and its pulse pattern
Time course
Eviction and return around dominant pregnancy
Shared data and research lineage
Shared research system; contraception and eviction studies are different designs.
Scope of the finding
Eviction was not randomized and cortisol mediation was not isolated by receptor blockade.
Source and corrections
Abbott et al. (1981)Component experimentFemale common marmosets; ten peer groupsMarmoset neuroendocrinology
Input or comparison
LH-RH, estrogen and TRH challenges
Measured change and output
Subordinates had anovulation and reduced LH-RH responsiveness without high cortisol or hyperprolactinemia.
Biological and contextual measurements
- Response to a GnRH challenge
- Cortisol or glucocorticoid metabolites
- Prolactin
Observed outcomes
- LH and its pulse pattern
- Ovulation or ovarian cycle
Time course
Established social groups and acute hormone challenges
Shared data and research lineage
Related research programme; repeated challenges and animals must not be counted as independent replications.
Scope of the finding
A reproductive-axis brake is not equivalent to a universal elevated-stress-hormone state.
Source and corrections
Abbott et al. (1988)Component experimentFive subordinate female marmosets in the relocation sequenceMarmoset neuroendocrinology
Input or comparison
Removal from subordination and reintroduction to subordinate groups
Measured change and output
Removal raised LH and estrogens before ovulation; renewed subordination lowered LH and stopped ovulation.
Biological and contextual measurements
- Social status, eviction or aggression
- LH and its pulse pattern
- Estradiol
Observed outcomes
- Ovulation or ovarian cycle
- Response to a GnRH challenge
Time course
LH returned to low levels within four days of renewed subordination
Shared data and research lineage
Related research programme; repeated challenges and animals must not be counted as independent replications.
Scope of the finding
Four days describes the LH fall after renewed subordination, not a universal fertility-loss time.
Source and corrections
Saltzman et al. (2004)Component experimentMarmoset families: 11 replacement and seven control familiesMarmoset neuroendocrinology
Input or comparison
Replace father with an unrelated male; remove and return father in controls
Measured change and output
Most daughters mated with the unfamiliar male; daughters conceived in 8/11 families, while ovulation reflected mother–daughter dominance.
Biological and contextual measurements
- Social status, eviction or aggression
- Partnered sexual activity
- Ovulation or ovarian cycle
Observed outcomes
- Pregnancy
- Availability of reproductive interactions
Time course
Family reorganization and subsequent reproduction
Shared data and research lineage
Related research programme; repeated challenges and animals must not be counted as independent replications.
Scope of the finding
Partner-directed behavior and ovarian readiness are linked but distinct gates.
Source and corrections
Burmeister et al. (2005)Component experimentAstatotilapia burtoni males; small genomic comparisonCichlid social plasticity
Input or comparison
Removal of the suppressing male before lights on
Measured change and output
Dominant behavior changed within 14 minutes and Egr-1 increased in the GnRH1-rich preoptic area.
Biological and contextual measurements
- Gene expression
- Social status, eviction or aggression
Observed outcomes
- Sexually directed interest
- Circuit activity or neural response
Time course
Minutes after social opportunity
Shared data and research lineage
Shared species and research programme; some hormonal assays reuse the same social-ascent animals.
Scope of the finding
The gene comparison used four ascending, three subordinate and three dominant fish; Egr-1 necessity was not tested.
Source and corrections
Eight axes, measured at different points in the sequence
The existing comparison axes become more informative when their measurements are joined within the same study or cohort. The table locates each axis as an input, receiving state, action or later outcome.
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| Comparison axis | Joint measurement | What existing evidence connects |
|---|---|---|
| Care allocation | Caregiving target and time × reproductive state × contact response | Prolactin-sensitive offspring contact and father–infant interaction locate different caregiving transitions. Clarkson 2026i; Weisman 2012i. |
| Dispersal and social proximity | Contact seeking × others’ response × realised contact × household transition | Sleep loss altered social distance and observer responses. PSID analyses connect sexual activity with relationships and living conditions in the same young adults. Ben Simon 2018i; Lei & South 2021i. |
| Stress and reproductive responsiveness | HPA dynamics alongside GnRH/LH response and ovulation | Marmoset status transitions locate LH and ovulation changes. Reproductive-axis responsiveness supplies a more specific measurement than inferring the same cortisol direction for every suppression pathway. Abbott 1988i. |
| Courtship and sexual motivation | Desire × partner-directed approach × sexual response × realised encounter | RFRP-3 changed sexually directed investigation selectively. Kisspeptin changed measured human sexual responses. These are distinct components of initiation and realisation. Peragine 2017i; Mills 2023i. |
| Signal production and reception | Specified sensory cue × receiver state × measured response | Queen odour supplies a defined chemical input in naked mole-rats; human infant-odour experiments measure reward-related responses. The shared level is the cue–receiver–response relationship. Khallaf 2026i; Lundström 2013i. |
| Social regulation | Sanction or support × contact availability × later action | Human network studies identify timed reproductive transitions after peer births. Together with interpersonal interventions, they constrain how others’ actions become a new opportunity structure. Balbo & Barban 2014i; Pink 2014i. |
| Hormonal and genomic change | Hormone and pulse timing × receptor response × fatherhood × sexual activity | The Cebu fatherhood and sexual-activity analyses share a cohort. Kisspeptin challenge under hyperprolactinaemia identifies a separate human pulse-response transition. Gettler 2011i; Gettler 2013i; Hoskova 2022i. |
| Risk, exploration and effort | Reward and effort choices × developmental stage × resources × later action | Dopamine and sleep interventions identify effort-related choices; PSID adds realised activities and life-course conditions. The observed task and the later demographic transition remain separately measured. Westbrook 2020i; Jurgelis 2022i; Lei & South 2021i. |
The strongest shared profile comes from several outcomes measured in the same individuals, followed through time. A household category, a caregiving target or a reported preference alone does not identify the receiving state. The eight axes organise these observations into a common causal question.
Three feedbacks connect the individual to population change
A change in behaviour becomes part of another individual’s sensory and social input. Repeated contact, reproduction and institutions can carry the change across different timescales.
Contact feedback
The person’s state changes their actions and how others respond. This changes the next set of available contacts, cues and learning experiences. Sleep-loss and father–infant interventions locate direct interpersonal transitions.
Reproduction and caregiving feedback
Births change access to infants and care. Contact changes later responsiveness and activity. Prolactin’s different targets show why stronger caregiving need not mean greater activation toward a new pregnancy.
Practice and institutional feedback
Repeated actions and reported reasons change shared practices, schedules, services and options encountered by later cohorts. Fertility-network observations locate timed social transmission; the broader institutional continuation is BERM synthesis.
A loop that strengthens the initial change is reinforcing feedback. Its persistence depends on the signs, strength and delays of the links. BERM already distinguishes physiological recovery, learning, social networks and institutional memory, so a population trajectory can persist after one acute biological measure has recovered.
The integrated conclusions and their sources
BERM synthesis across studies
Selective reproductive regulation
Reproductive activation, sexual interest and retained physiological reserve are coordinated but separable outputs of biological regulation.
Scope of the connection: Protocol-specific component directions support the structure; they do not identify a common field dose or universal suppression score.
BERM synthesis across studies
Caregiving and reproductive allocation
A shared hormonal state can engage different receptor and circuit targets, preserving or increasing care while another reproductive output is restrained.
Scope of the connection: PRL suppression and PRL-receptive care circuits are separate component experiments; pet ownership and childlessness are not suppression diagnoses.
BERM synthesis across studies
From motivation to realized encounters
Biologically formed motivation and others’ responses help determine realized encounters and conception attempts, separately from the capacity to conceive.
Scope of the connection: Human joint-output and interaction data support the intermediate structure; the complete hormonal-to-birth route is a composition.
BERM synthesis across studies
Social feedback and population timing
Individual states change social cues and network opportunities; responses of other biological agents feed back into later reproductive timing.
Scope of the connection: Network associations provide timing constraints, not measured endocrine mediation or a calibrated civilization feedback coefficient.
Existing data that can join the measurements
The resources below retain their population, time window, access conditions and measured variables. Published analyses and available data support the structural integration without assigning unobserved hormone or field values to individuals.
Wild meerkats; 12 groupsKalahari meerkat studies
Contraception versus saline in a crossover design
Collection years: 2009–2011
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: Group opportunities and pregnancy costs also changed; the experiment does not isolate intrinsic caregiving motivation.
Subordinate female meerkatsKalahari meerkat studies
Natural eviction followed longitudinally; GnRH challenge
Publication year: 2006
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: Eviction was not randomized and cortisol mediation was not isolated by receptor blockade.
Female common marmosets; ten peer groupsMarmoset neuroendocrinology
LH-RH, estrogen and TRH challenges
Publication year: 1981
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: A reproductive-axis brake is not equivalent to a universal elevated-stress-hormone state.
Five subordinate female marmosets in the relocation sequenceMarmoset neuroendocrinology
Removal from subordination and reintroduction to subordinate groups
Publication year: 1988
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: Four days describes the LH fall after renewed subordination, not a universal fertility-loss time.
Marmoset families: 11 replacement and seven control familiesMarmoset neuroendocrinology
Replace father with an unrelated male; remove and return father in controls
Publication year: 2004
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: Partner-directed behavior and ovarian readiness are linked but distinct gates.
Astatotilapia burtoni males; small genomic comparisonCichlid social plasticity
Removal of the suppressing male before lights on
Publication year: 2005
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: The gene comparison used four ascending, three subordinate and three dominant fish; Egr-1 necessity was not tested.
Astatotilapia burtoni social ascentCichlid social plasticity
Social ascent with time-resolved endocrine measurements
Publication year: 2011
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: Later 6–120-hour trajectories differ by endpoint; associated 11-ketotestosterone data reuse previously published animals.
60 Astatotilapia burtoni males across three time pointsCichlid social plasticity
Larger male visible across a watertight transparent barrier
Publication year: 2011
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: Visible behavior does not identify the full physiological state; testis-size differences were not significant.
Socially suppressed Astatotilapia burtoni malesCichlid social plasticity
Release from social suppression and fertility testing
Publication year: 2012
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: Suppressed reproductive activity did not mean loss of all gonadal reserve.
Naked mole-rats, Heterocephalus glaberMole-rat peptide and release studies
Central RFRP-3 infusion after removal from the colony
Publication year: 2017
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: Testosterone differences were not significant; sufficiency of the administered peptide is not proof of endogenous necessity.
Female naked mole-rat helpersMole-rat caregiving cues
Pregnant queen feces or estrogen-supplemented fecal material
Publication year: 2018
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: The endpoint was pup-cue responsiveness, not total caregiving or a demonstration that infertility automatically creates care.
Naked mole-rat pairs and queenless colonyMole-rat odour and endocrine studies
Queen-enriched isopropyl myristate, colony bedding and withdrawal
Publication year: 2026
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: A chemical cue experiment is not EMF dose equivalence; the colony withdrawal is not a multi-colony replication.
24 female naked mole-rats from 12 coloniesMole-rat odour and endocrine studies
GnRH challenges, ovariectomy, handling and naloxone
Publication year: 2024
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: Repeated assays share animals; some smaller-worker comparisons reuse earlier Faulkes data.
Naked mole-rat pairs after colony removalMole-rat peptide and release studies
Removal, pairing and longitudinal reproductive follow-up
Publication year: 2025
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: The 26-pair analysis includes the eight focal pairs plus 18 earlier Toor pairs. Nonbreeding within a year is not permanent damage.
Naked mole-rat pairs after colony removalMole-rat peptide and release studies
Removal, pairing and longitudinal reproductive follow-up
Publication year: 2025
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: The 26-pair analysis includes the eight focal pairs plus 18 earlier Toor pairs. Nonbreeding within a year is not permanent damage.
Hyperprolactinemic female miceProlactin–kisspeptin mouse studies
Chronic prolactin exposure and kisspeptin rescue
Publication year: 2012
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: A localized endocrine rescue; not a human caregiving or environmental-field experiment.
11 women with hyperprolactinemiaHuman hyperprolactinemia studies
Two 12-hour visits; repeated kisspeptin on the second visit
Publication year: 2022
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: Use corrected version of record; the study did not demonstrate ovulation, pregnancy or caregiving change.
Prolactin-receptive mouse MPOA–VTA circuitProlactin-receptive caregiving circuits
Circuit activation and removal of prolactin action
Publication year: 2026
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: The caregiving circuit and endocrine suppression studies are separate experiments joined by a shared hormone.
Mouse MPOA galanin neurons and projectionsParental circuit architecture
Projection-specific optogenetic interventions
Publication year: 2018
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: A structured caregiving programme is not one undifferentiated motivation variable.
Pregnant and nonpregnant female miceParental circuit architecture
Pregnancy-hormone and parental-circuit manipulation
Publication year: 2023
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: Circuit history adds persistence to acute hormonal regulation; not evidence of permanent suppression.
400 healthy men aged 20–50 in two cohortsGonadal steroid suppression and replacement
Gonadal suppression, randomized testosterone doses and aromatase inhibition
Publication year: 2013
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: A causal hormone-to-function anchor, without calibrated environmental-field transfer.
37 randomized men with HSDD; 32 completed both visitsKisspeptin and sexual processing
Blinded kisspeptin versus placebo crossover
Collection years: 2021
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: Distinct neural, physiological and subjective endpoints; no measured child-desire or conception-attempt outcome.
40 randomized women with HSDD; 32 completed both visitsKisspeptin and sexual processing
Kisspeptin–placebo crossover in the early follicular phase
Collection years: 2020–2021
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: A neural response is not proof of a broad clinical desire or fertility improvement.
Cebu fatherhood and testosterone follow-upCebu fatherhood cohort
Shared 2005 and 2009 male cohort measurements
Collection years: 2005, 2009
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: The 624-person fatherhood report and 433-person sex report overlap; biomarkers are not assumed unrestricted.
35 father–infant dyads; infants about five months oldFather–infant hormonal interaction
Paternal intranasal oxytocin–placebo crossover
Publication year: 2012
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: Dyadic transfer is measured; later papers reuse this cohort rather than providing independent replication.
NSSHB ages 14–49; 4,155 in 2009 and 4,547 in 2018National Survey of Sexual Health and Behavior
Repeated cross-sections and latent classes of sexual behavior
Collection years: 2009
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: Question-specific denominators differ; adult 72.7% versus 72.5% solo activity was not a significant change.
NSSHB ages 14–49; 4,155 in 2009 and 4,547 in 2018National Survey of Sexual Health and Behavior
Repeated cross-sections and latent classes of sexual behavior
Collection years: 2018
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: Question-specific denominators differ; adult 72.7% versus 72.5% solo activity was not a significant change.
3,213 US adults aged 18–23; fixed-effect subset 655PSID transition to adulthood
Longitudinal PSID-TAS mediation and within-person analysis
Collection years: 2007–2017
Access: Public data are free after registration; participant identifiers link waves.
Measurement scope: Measured mediation is not demonstrated hormonal mediation or environmental-field attribution.
Human sleep-loss experiment and independent video observersSleep and social interaction
Sleep deprivation and social-distance judgments
Publication year: 2018
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: The interaction-opportunity bridge is measured; mate formation and reproduction are a further conditional continuation.
Dogs, human caregivers and hand-raised wolvesHuman–dog affiliative feedback
Mutual gaze observation and canine oxytocin–placebo intervention
Publication year: 2015
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: No child-desire, human infertility or replacement-parenthood endpoint; urinary oxytocin is not a direct brain concentration.
Add Health friendship and parenthood recordsAdd Health friendship networks
Longitudinal observational network analysis
Publication year: 2014
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: Selection and shared context require modelling; no hormonal mediator was measured.
33,119 women in 6,579 German firmsGerman workplace fertility records
Linked employer–employee fertility histories
Collection years: 1993–2007
Access: Published methods and results are available; unrestricted participant-level access is not asserted.
Measurement scope: Observational workplace propagation; not a neural or hormonal intervention.
NHANES hormones and behaviorNHANES examination surveys
Join TST_H, SXQ_H, RHQ_H, SLQ_H and DEMO_H by SEQN.
Collection years: 2013–2014
Access: Official documentation and access route; account or restricted-data terms may apply.
Measurement scope: Use common age/assay eligibility and weights; assay conversion is needed for some cross-cycle testosterone comparisons.
NSHAP biomarkers and social lifeNSHAP aging and social life
Repeated salivary sex hormones, sexual interest and social-network measurements.
Collection years: 2005–2006; 2010–2011
Access: Official documentation and access route; account or restricted-data terms may apply.
Measurement scope: Wave 1 includes over 3,000 adults aged 57–85; public and restricted files differ.
NSFG intentions, activity and family historyNational Survey of Family Growth
9,957 respondents: 5,586 women and 4,371 men aged 15–49.
Collection years: 2022–2023
Access: Official documentation and access route; account or restricted-data terms may apply.
Measurement scope: Use both survey years and weights; historical comparisons often restrict to 15–44. No measured hormones.
GSS behavior and attitudesGeneral Social Survey
Sexual activity, family and selected attitudes in shared questionnaire records.
Collection years: 1972–2024
Access: Official documentation and access route; account or restricted-data terms may apply.
Measurement scope: Verify form overlap and the changed 2024 PARTNERS coding; cumulative cross-sections are not a single-person panel.
MTF youth behavior profilesMonitoring the Future
6,895 grade-12 respondents with six randomized forms and a common core.
Collection years: 2024
Access: Official documentation and access route; account or restricted-data terms may apply.
Measurement scope: All variables are not measured in every respondent; school surveys and the separate adult panel differ.
Pew child expectations and social contextPew American Trends Panel
Reported reasons, pressure, social ties and caregiving among selected adults without children.
Collection years: 2024-04-29–2024-05-19
Access: Official documentation and access route; account or restricted-data terms may apply.
Measurement scope: The 57% reason statistic concerns 18–49-year-olds already expecting no future children, with multiple reasons permitted.