American scientists have issued a warning to potential parents to avoid one month of the year in particular when they are trying for a new baby.
Researchers from the University of Indiana say that the worst time of the year to try and start your family is June, and have even named it ‘the toxic June effect’.
The scientists believe that large quantities of pesticides sprayed on crops in the summer months are partially to blame for it being the most ‘vulnerable stage’ for potential mothers - making summer mummies the most likely to have short pregnancies and premature babies.
This pesticide problem is combined with lower levels of sunlight and Vitamin D exposure towards the end of the pregnancy around February and March.
And despite shops telling us we should be rekindling passions in our relationships in late February, scientists say Valentines' Day on 29 February is one of the least likely times to conceive.
On the contrary, Christmas is the peak time in the calendar for conceiving, with the month of December being the best time for successful pregnancies.
The research found that an extra 3 babies in every 200 pregnancies survive if conceived in December.
They believe that just as low sunlight affects June mothers, the December mothers-to-be are exposed to high levels of summer sunshine at a late stage of the birth.
Higher levels of Vitamin D not only help with a smooth birth, but it maintains healthy bones and is thought to protect against cancer, Type 1 diabetes and multiple sclerosis.
The revealing study was conducted at Indiana University for five years between 2004 and 2009 and involved 270,000 pregnancies.
These findings also fit with results from the University of Cambridge, which showed that babies born in the summer were likely to be stronger and taller.
