The effect of intercourse on pregnancy rates during assisted human reproduction

Abstract

Intercourse during an IVF cycle has the potential to improve pregnancy rates since exposure to semen is reported to promote embryo development and implantation in animals. Conversely, coitus-induced uterine contractions or introduction of infection may have a detrimental effect. A multicentre prospective randomized control trial was conducted to determine if intercourse during the peri-transfer period of an IVF cycle has any influence on pregnancy success. Participants undergoing thawed embryo transfer (Australian centre) or fresh embryo transfers (Spanish centres) were randomized either to abstain or to engage in vaginal intercourse around the time of embryo transfer. The transfer of 1343 embryos during 478 cycles of IVF resulted in 107 pregnancies (22.4%), with 125 viable embryos remaining by 6-8 weeks gestation. There was no significant difference between the intercourse and abstain groups in relation to the pregnancy rate (23.6 and 21.2% respectively), but the proportion of transferred embryos that were viable at 6-8 weeks was significantly higher in women exposed to semen compared to those who abstained (11.01 versus 7.69 viable embryos per 100 transferred embryos, P = 0.036, odds ratio 1.48, 95% confidence interval 1.01-2.19). Hence exposure to semen around the time of embryo transfer increases the likelihood of successful early embryo implantation and development.

Seminal fluid and reproduction: much more than previously thought

“…More recently this work has been carried over into the human ART program. It has been shown that semen exposure around the time of embryo transfer increases the rates of embryo implantation and possible subsequent foetal development [5,115,116]. Bellinge et al has previously shown that seminal exposure as early as the time of oocyte retrieval can increase the incidence of pregnancy in women undergoing IVF [117].…”

“…Thus it appears that seminal factors act primarily to optimise the likelihood of successful pregnancy. This has been supported by studies showing the addition of seminal plasma or seminal factors to assisted reproductive procedures can markedly improve pregnancy success in mice, rats, hamsters, sheep and humans [2][3][4][5][6].…”

Dizygotic twin pregnancy after single embryo transfer: a case report and review of the literature

“…However, advice against intercourse around the time of embryo transfer is not typically given because it might have a positive effect on the pregnancy outcome. Only two studies have investigated the effects of vaginal intercourse around the time of embryo transfer during ART cycles [17,18]. Tremellen et al reported that, in a multicenter randomized study, patients undergoing fresh (400 cycles) and frozen-thawed (200 cycles) embryo transfer were randomized either to abstain or to engage in vaginal intercourse around the time of embryo transfer.…”

Effect of seminal plasma application to the vaginal vault in in vitro fertilization or intracytoplasmic sperm injection treatment cycles—a double-blind, placebo-controlled, randomized study

“…They described an implantation rate of 80 % (35/44) in patients in the SP group, compared with one of 67 %( 29/43) in the placebo group. Tremellen et al [10] randomized patients during 478 cycles of IVF (including transfer of 1343 embryos) either to abstain from or engage in vaginal intercourse and found similar pregnancy rates (21.2 % vs 23.6 %, respectively) but a significantly higher proportion of viable embryos at 6-8 weeks of pregnancy in the group engaging in vaginal intercourse (11 % vs 7.7 %). Finally, von Wolff et al, [11] performed a pilot study, injecting cryopreserved seminal plasma from the patient's partner or sodium chloride (placebo) into the cervix and the posterior fornix of the vagina just after follicle aspiration.…”

“…SP contains a variety of factors such as Transforming Growth Factor b, [1,4], prostaglandin E and interleukin-8 [7], that may trigger a cascade of events through pro-inflammatory cytokines synthesis leading to maternal endometrial immunomodulation increasing uterine receptivity. A beneficial effect of SP as an adjunctory factor to increase implantation and clinical pregnancy rates after in vitro fertilization and embryo transfer (IVF-ET) was indicated in a few clinical studies that used variable methodologies [8][9][10][11]. Others did not corroborate these observations [12].…”