Male birthweight, semen quality and birth outcomes

Abstract

STUDY QUESTION: What are the relations among birthweight (BW), semen parameters and birth outcomes in a population-based sample?SUMMARY ANSWER: BW is unrelated to semen parameters, which are in turn unrelated to birth outcomes. WHAT IS KNOWN ALREADY:In clinical settings, there has been suggestion that semen parameters are related to BW when comparing fertile and infertile men; however, findings have been less clear in more general populations.STUDY DESIGN, SIZE, DURATION: Questionnaire data and semen samples were collected at baseline from 427 male participants of the population-based Longitudinal Investigation of Fertility and the Environment (LIFE) prospective cohort study from 2005 to 2009, who were followed prospectively to assess pregnancy outcomes among 226 singleton births. PARTICIPANTS/MATERIALS, SETTING, METHODS:Men of at least 18 years of age who were married or in a committed relationship and trying to conceive were eligible for participation; physician-diagnosed infertility was an exclusion criterion. Participants were recruited from two geographic areas and semen samples were analyzed for 34 quality parameters categorized as general, motility, morphology, sperm head and sperm chromatin structure using methods including computer-aided semen analysis integrated visual optical system and sperm chromatin structure assay. Linear and mixed models were used for statistical analysis of the relations between men's BW, semen parameters, and BW, gestational age at delivery, birth length, head circumference and ponderal index of singleton births. MAIN RESULTS AND THE ROLE OF CHANCE:No association was observed between male BW and semen parameters or birth outcomes. Few associations were observed between semen parameters and birth outcomes, and the observed statistically significant associations were isolated and without a consistent pattern that would suggest an association between BW and birth outcomes.LIMITATIONS, REASONS FOR CAUTION: Men's BW was self-reported and may be subject to some imprecision. Semen analysis was performed the day after collection, an approach that impacts the assessment of motility and that may limit inference from our analyses of motility measures. In addition, inclusion criteria for selection into the cohort limits generalizability to generally healthy couples trying to conceive and without known subfertility. WIDER IMPLICATIONS OF THE FINDINGS:Despite suggestions from prior studies of male in utero exposures impacting BW and male reproductive health, there appears to be little support for such relations in this generally healthy population.

Relationship between male age, semen parameters and assisted reproductive technology outcomes

“…Much of our data is in agreement with the literature in that there are minimal effects of abnormal spermatozoa on ART outcomes and those that are observed are not consistent. Among men enrolled in the Longitudinal Investigation of Fertility and the Environment (LIFE) study, there were 226 singleton births with associated paternal semen parameters 26 . Overall, there were no significant effects of individual semen parameters (eg motility, morphology, TMC) on both birth weight and gestational age at time of delivery.…”

Infertility in Men in Relation to Their Birth Characteristics

“…Sperm concentration (10 6 per ml) 16 (15)(16)(17)(18) Total sperm number (10 6 per ejaculate) 39 (35)(36)(37)(38)(39)(40) Total motility (PR+NP, %) 42 (40)(41)(42)(43) Progressive motility (PR, %) 30 (29)(30)(31) Non-progressive motility (NP, %) 1 (1-1)…”

Birth characteristics in men with infertility

“…Although these data on non-optimal birth characteristics (used as a groupingterm for PTB, LBW and SGA) are risk factors for lower reproductive rate, it is still uncertain whether birth weight is associated with semen quality or with other causes of subfertility. Sperm parameters did not seem to be related to birth weight when analysing semen samples from men without a diagnosis of infertility (Ramlau-Hansen et al, 2010;Whitcomb et al, 2017). In a study of men with unexplained infertility, all born at term with normal birth weight (>2500 g), birth weight was inversely correlated to total sperm count and positively correlated to sperm fragmentation (Faure et al, 2015).…”