Since Jenny Madestam noted the low share of female party leaders in Sweden historically and in the present, why not take a short look at Denmark.
If we concentrate on parties which are or have been represented in the Folketing, we get this list with the data available on Wikipedia:
Social Democrats: Helle Thorning-Schmidt (2005- )
Danish People’s Party: Pia Kjærsgaard (1995- )
Conservative People’s Party: Pia Christmas Møller (1998-1999)1, Lene Espersen (2008-2011)
Social Liberal Party: Marianne Jelved (1990-2007), Margrethe Vestager (2007- )2
Red-Green Alliance: Collective leadership, but Johanne Schmidt-Nielsen is the party’s political spokesman
New/Liberal Alliance: (None)
Christian Democrats: Marianne Karlsmose (2002-2005), Bodil Kornbek (2005-2008)
Progress Party: Annette Just (1985-1986)3
Centre Democrats: Mimi Jakobsen (1989-2005)
Left Socialists: (Collective leadership)
Communist Party: (None)
If we look at the present Folketing, four out of nine parties (if we include the Christian Democrats) have female leaders or spokesman. At the same time, this is very much a phenomenon of the 1990s and 2000s.
The next question is if the female party leaders – as well as female politicians – feel that they have been treated differently than their male counterparts in parliament, in the media and in public. This is probably more difficult to answer even if Ekstra Bladet – of all newspapers – broke this story back in 2008.
What we can note, is that both female leaders of the Conservatives have met untimely ends to their terms in office while gender appears not to be an issue in the Social Liberal Party. The Danish equivalent of the term “chairwoman” or “chairperson” has never been widely used: Helle Thorning Schmidt is the chairman (formand) of the Social Democrats.