The revamped version of Prime Minister Shinzo Abe's growth strategy will likely call on companies and state entities to insert more women into senior positions and aim to improve public child care support to shore up Japan's shrinking workforce.

But if Abe wants to bring out working mothers' full potential, he should address child care needs that can arise from unexpected situations, according to Keiko Koda, head of AsMama, a Yokohama-based startup that acts as a matchmaker for mothers offering and seeking child care services.

For example, a mother at work may get an unexpected phone call from the nursery asking her to pick up her boy because he is showing cold symptoms. Or her daughter in elementary school might call to say she's been locked out of the house and waiting to be let in. Or the mother herself may have trouble getting to the nursery on time due to a train delay.