The latest research by American scientists indicates that drinking alcohol – especially during the period after ovulation – is associated with lower chances of getting pregnant. It is well known that excessive consumption of alcoholic beverages may adversely affect fertility. Interestingly, recent reports suggest that even moderate drinking reduces the chances of conceiving a child.
The study published in June 2021 in Human Reproduction (one of the leading journals in reproductive medicine) focused on alcohol consumption and fertility, defined as the probability of conceiving a child during a single menstrual cycle. This was the first study to look at the effects of alcohol in relation to different phases of the menstrual cycle.
A research team from the University of Louisville School of Public Health and Information Sciences (Kentucky, USA) analyzed the data collected in the 1990s during a large health study of 413 women aged 19-41 years. Participants were followed for up to 19 menstrual cycles. The women completed diaries in which they recorded how much alcohol they drank and what type and provided urine samples on the first and second day of each cycle to check for pregnancy.
For the purpose of this study, the number of drinks consumed (one drink = 1/3 of a liter of beer (355 ml) or a medium glass of wine (148 ml) or just under a double serving of spirits (44 ml) was used as the measure. Alcohol consumption was analyzed by three categories: binge drinking – defined as more than 6 drinks per week, moderate drinking – 3 to 6 drinks per week, heavy drinking – more than 4 drinks in one day. Researchers additionally took into account information about factors that might influence the results, such as age, medical history, smoking, obesity, contraceptive use and intent to become pregnant.
The study found that heavy drinking during any phase of the menstrual cycle may be significantly associated with a reduced likelihood of conception compared to non-drinkers. This is important because some women trying to get pregnant may think it is “safe” to drink alcohol during certain phases of the cycle.
During the luteal phase, the last two weeks of the menstrual cycle before bleeding begins and when implantation occurs, not only heavy drinking but also moderate drinking was significantly associated with a reduced likelihood of conception.
Compared with non-drinkers, both moderate and excessive alcohol consumption during the luteal phase was associated with a reduction in the odds of conception of about 44%. Intense drinking during the ovulatory part of the cycle was also associated with a significant, 61% reduction in the chance of pregnancy. The researchers stress, however, that these are estimates and should be treated with caution.
The conclusion is simple – if you are trying to get pregnant avoid drinking alcohol more than occasionally.