Check out this author's intriguing theory—best tested by parents of large families—about the relationship between the moon phase and when a mother gives birth.
During the lunar month (29.5 days), the moon's shape is different every day. The apparent shape of a waxing moon can be matched with a waning moon to appear as a perfect circle. The two shapes that match appear in the sky about two weeks apart. They might be called moonmates. The first and third quarters are mates; the full and new moons are likewise mates. Moonmates, in addition to being reciprocals in shape, also offer valuable lessons to man. For instance, moonmates produce the same gravitational pull on the earth, as evidenced in tides.
While working on tide charts, I stumbled on a very important relationship between the age of the moon and the birth of babies. The age of the moon refers to a specific point in the lunar cycle, with the day of the new moon being zero, the next day one, and so on. (The moon waxes for 14-plus days, and after full it wanes for 14-plus days). I checked out the age of the moon for the day of my birth and found the moon was ten days old. I checked my brother out. Ten days old. Just a coincidence, thought I. So I decided to dig a little deeper. My wife gave birth to three children, one in 1932, the second in 1934, and the last one (17 years later!) in 1951. All three were born when the moon was six days old!
These three children all married, and my wife and I have been blessed with nine grandchildren. Seven of the nine followed the pattern — of the two that didn't, one was premature and the other was delivered by Caesarean section. One of my neighbors had eight children and another had six. They all arrived on the same moon day OR on the moonmate day. Every woman seems to have her day. My mother's day was 10. My wife's day was 6. My neighbor's day was 24.
There is a need here for further study, but I believe that if a woman's first child has a normal birth she can help to predict the arrival date of future children by using the moon phase calendar. Those who like to play the favorite guessing game of predicting the new baby's birthday now have some help.