Stories
Slash Boxes
Comments

SoylentNews is people

posted by Fnord666 on Thursday February 20 2020, @10:39AM   Printer-friendly
from the how-many-september-births-are-christmas-presents? dept.

Late Fall May Be Best Time of Year to Try to Conceive:

The first-of-its-kind study, published in the journal Human Reproduction, finds that, although couples in North America and Denmark are most likely to start trying in September, it's in late November and early December that they have the best chances of conceiving, especially at lower latitudes.

"There are a lot of studies out there that look at seasonal patterns in births, but these studies don't take into account when couples start trying, how long they take to conceive, or how long their pregnancies last," says study lead author Amelia Wesselink, postdoctoral associate in epidemiology.

"After accounting for seasonal patterns in when couples start trying to conceive, we found a decline in fecundability in the late spring and a peak in the late fall," she says. ("Fecundability" refers to the odds of conceiving within one menstrual cycle.) "Interestingly, the association was stronger among couples living at lower latitudes."

[...] season affected fecundability for North Americans by 16 percent, while Danes got only an 8-percent seasonal boost in the fall and dip in the spring. In Southern US states, the seasonal variation was even stronger, at 45 percent, with a peak in quick conceptions in late November. Meanwhile, the relationship between season and fecundability turned out to be about the same in Denmark and in Northern states and Canada.

The study used data on 14,331 pregnancy-planning women who had been trying to conceive for no more than six months, including 5,827 US and Canadian participants in the SPH-based Pregnancy Study Online (PRESTO) and 8,504 Danish participants in the Snart Gravid and Snart Foraeldre studies based at Aarhus University in Denmark. These studies follow women with detailed surveys every two months until they either conceive or have tried to conceive for 12 menstrual cycles, gathering data on everything from intercourse frequency and menstruation, to smoking and diet, to education and income.

[...] "Although this study cannot identify the reasons for seasonal variation in fertility, we are interested in exploring several hypotheses on seasonally-varying factors and how they affect fertility, including meteorological variables such as temperature and humidity, vitamin D exposure, and environmental exposures such as air pollution," Wesselink says.

Journal Reference:
Amelia K Wesselink, et al. Seasonal patterns in fecundability in North America and Denmark: a preconception cohort study. Human Reproduction, 2020; DOI: 10.1093/humrep/dez265


Original Submission

 
This discussion has been archived. No new comments can be posted.
Display Options Threshold/Breakthrough Mark All as Read Mark All as Unread
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
  • (Score: 2) by DannyB on Thursday February 20 2020, @03:19PM (8 children)

    by DannyB (5839) Subscriber Badge on Thursday February 20 2020, @03:19PM (#960296) Journal

    NOT Late Fall may be the best time to try to NOT conceive.

    --
    People today are educated enough to repeat what they are taught but not to question what they are taught.
    Starting Score:    1  point
    Karma-Bonus Modifier   +1  

    Total Score:   2  
  • (Score: 0) by Anonymous Coward on Thursday February 20 2020, @03:32PM (3 children)

    by Anonymous Coward on Thursday February 20 2020, @03:32PM (#960304)

    Or as a friend once described his gf -- she doesn't want to have babies, but she does like to practice.

    • (Score: 0) by Anonymous Coward on Thursday February 20 2020, @10:14PM (2 children)

      by Anonymous Coward on Thursday February 20 2020, @10:14PM (#960465)

      She likes to practice having babies? Sounds like a lot of trouble for anyone go through the trouble of 9 months of pregnancy, then labor and childbirth, on purpose and then not get anything at the end.

      • (Score: 0) by Anonymous Coward on Friday February 21 2020, @01:28AM (1 child)

        by Anonymous Coward on Friday February 21 2020, @01:28AM (#960543)

        Tough crowd tonight, you leave a hole and they fall right into it.

        How about: friend's GF doesn't want to conceive, but likes to practice. Does that close up the hole for you?

        • (Score: 0) by Anonymous Coward on Friday February 21 2020, @07:46AM

          by Anonymous Coward on Friday February 21 2020, @07:46AM (#960626)

          Doesn't want to conceive, likes to practice, close the hole. Oh, I got it. Front entrance is closed for deliveries, please use the loading zone located in the rear.

  • (Score: 2, Interesting) by khallow on Thursday February 20 2020, @03:58PM (3 children)

    by khallow (3766) Subscriber Badge on Thursday February 20 2020, @03:58PM (#960319) Journal
    Or maybe we have yet another study that has failed to take said seasonal patterns in when couples try to conceive into account.
    • (Score: 2) by DeathMonkey on Thursday February 20 2020, @06:34PM (2 children)

      by DeathMonkey (1380) on Thursday February 20 2020, @06:34PM (#960391) Journal

      That would be a pretty big miss for a paper called "Seasonal patterns in fecundability in North America and Denmark: a preconception cohort study!"

      • (Score: 1) by khallow on Friday February 21 2020, @05:12AM

        by khallow (3766) Subscriber Badge on Friday February 21 2020, @05:12AM (#960592) Journal
        Wouldn't be the first big miss.
      • (Score: 1) by khallow on Friday February 21 2020, @01:32PM

        by khallow (3766) Subscriber Badge on Friday February 21 2020, @01:32PM (#960664) Journal
        To elaborate on my previous reply, the reason such biases are present in the first place is because it's a hard problem to remove them, and I wouldn't be surprised, since it's happened before, that the authors didn't actually succeed. Certainly with so many big differences between the test groups, I wouldn't look at latitude as being a significant contributor, particularly when it's supposed to contribute the most when it's the least relevant (the group with the least seasonal variation)? Something else is afoot. Maybe the study overcorrected for the effects of seasonal variation and thus, is showing an effect where none exists.