I'm pretty sure that wartime birth rates were quite high.
I think you are right
US Birth rates
United Kingdom
In the
United Kingdom the baby boom occurred in two waves. After a short first wave of the baby boom during the war and immediately after, peaking in 1946, the United Kingdom experienced a second wave during the 1960s, with a peak in births in 1964.
Ireland
The baby boom in Ireland began during the state of
emergency which existed in the country during the
Second World War.Laws on contraception were restrictive in Ireland and the baby boom was more prolonged in this country. Secular decline of fertility began only in the 1970s and particularly after the
legalization of contraception in 1979. The marriage boom was even more prolonged and did not recede until the 1980s.
Western Europe
France and Austria experienced the strongest baby booms in Europe. In contrast to most other countries, the French and Austrian baby booms were driven primarily by an increase in marital fertility.In the French case, pronatalist policies were an important factor in this increase.
[35] Weaker baby booms occurred in Germany, Switzerland, Belgium and the Netherlands
Southern Europe
Baby boom was absent or not very strong in Italy, Greece, Portugal and Spain. There were however regional variations in Spain with a considerable baby boom occurring in such regions as
Catalonia
Eastern Europe
There was a strong baby boom in Czechoslovakia, but it was weak or absent in Poland, Bulgaria, Russia, Estonia and Lithuania, partly as a result of the
Soviet famine of 1946–47.
Nordic countries
The baby boom was very strong in Norway and Iceland, significant in Finland, moderate in Sweden and relatively weak in Denmark.
[17]
Asia and Africa
Along with the developed countries of the West, many developing countries (among them Morocco, China and Turkey) also witnessed the baby boom.The baby boom in Mongolia, one of such developing countries, is probably explained by improvement in health and living standards related to the establishment of a socialist society.
Latin America
The baby boom also occurred in most Latin American countries (with the exception of Brazil, Argentina and Uruguay). An increase in fertility was driven by a decrease in childlessness and, in most nations, by an increase in parity progression to second, third and fourth births. Its magnitude was largest in Costa Rica and Panama.
Source: wiki