Women who consumed fruit just 1-3 times per month versus those that consumed it at least 3 times daily corresponded to a 19% increase in median time to pregnancy.
Dr. Jessica Grieger
Both fruit and fast food intake may influence women’s fertility.
A new study from the Robinson Research Institute, University of Adelaide, Australia, has found that lower intakes of fruit as well as a higher intake of fast food by women in the period of preconception were associated with a longer time to pregnancy (TTP) than average. The findings add to the evidential list of lifestyle factors — such as smoking and obesity — that have been linked to longer TTP or even infertility, regardless of other health conditions.
Researchers, led by Dr. Jessica Grieger, conducted a multi-center pregnancy-based cohort study of 5598 nulliparous women with low-risk singleton pregnancies who previously participated in the Screening for Pregnancy Endpoints (SCOPE) study. Data on retrospective TTP and preconception dietary intake for each of the participants were collected in the first antenatal study visit — which occurs 14-16 weeks into gestation.
A research midwife would obtain diet frequency rates for fruits, leafy vegetables, fish, and fast food items for the month prior to conception. Just 340 (6%) of all observed women were using fertility treatments at the time of analysis. The impact of dietary differences to infertility rates — which was defined as TTP being more than 12 months — was compared using a generalized linear model with wide variance estimates, relative risks, and 95% CIs.
Results showed that both lower intakes of fruit and greater intakes of fast food were associated with modest increases in TTP and infertility risk. Women who consumed fruit just 1-3 times per month versus those that consumed it at least 3 times daily corresponded to a 19% increase in median TTP (P = 0.007). Even women who consumed fruit 1-6 times per week corresponded to a 11% increase in media TTP compared to the latter group (P = 0.007).
For women who consumed fast food at least 4 times per week, a corresponding 24% increase in median TTP was reported when compared to those who consumed no fast food (P < 0.001). In comparison of the same 2 groups, infertility risk was raised 41% in the former group (P <0.001). However, researchers noted the pre-pregnancy diets of leafy vegetables or fish were not associated with TTP or infertility.
Though research was limited by its selected range of foods — and did not at all take into account paternal diets — the findings emphasize the need to consider preconception diet. It also contributes to previous findings that women’s preconception or at-pregnancy intake or health status can heavily influence their child’s immediate health at birth.
According to a study from the National Institutes of Health (NIH) last year, artificially sweetened beverages during pregnancy increase the risk of a child developing early obesity. Another study from 2017 found that an expecting mother’s obesity correlates with infant macrosomia.
On Monday, US Food and Drug Administration (FDA) commissioner Scott Gottlieb, MD, announced the nationwide implementation of calorie counts listed next to eating establishment menus. He also encouraged consumers to request more nutritional information at such venues, as the administration advances its Nutrition Innovation Strategy over the next coming years.
“The Nutrition Innovation Strategy will modernize claims like “healthy” on food packages, modernize how we establish standards of identity for foods, make ingredient information on labels easier to decipher, help streamline the process for establishing qualified health claims on food labels, and encourage companies to reduce sodium in their products,” Gottlieb said in a statement.
As to how diet and nutrition influences preconception status, researchers wrote that further analysis across a broader range of foods and food groups will be necessary moving forward.
The study, "Pre-pregnancy fast food and fruit intake is associated with time to pregnancy," was published online in Human Reproduction this week.